My xj8 drives great for about an hour or a little less after that restricted performance comes on then goes away. But then soon after it will start to sputter when I press the accelerate and barely moves. It moves faster with out me pressing the accelerator. Received P0172 and P0175 codes along with misfire on cyclinders 1-4. I was thinking oxygen sensor. could it be mass flow sensor?

 

Cleaning the MAF certainly won't hurt, I'd clean it then reset codes.

 

I would concur with a possible MAF gone south. But as KC said, try cleaning first, but use MAF only cleaner.

 

Thanks guys. I'll try it.

 

Update: I cleaned the mass air flow sensor. I don't have the sputters or restricted performance issue. I think I will replace it although.